<template>
  <div v-bind:class="isRed?'active':'noActive'">fdfdfdfd</div>
</template>
<script>
export default {
  data() {
    return {
      isRed: false
    };
  }
};
</script>
<style>
.active {
  background: red;
}
.noActive {
  background: blue;
}
</style>
